For the cutting of steel, cast iron, stainless steel, heat-resistant alloys, etc., a surface coated cutting tool has been widely employed which comprises, on a surface of a substrate consisting of cemented carbide, cermet, cBN or the like, one layer or two or more layers each comprised of a hard coating, such as a TiN film or a TiAlN film.
For example, Japanese Translation of PCT Application No. 2015-530270 proposes a tool in which TiSiN layers and AlCrN layers are alternately laminated on a main body made of cemented carbide, cermet, ceramic, steel, or high-speed steel so that each layer has a thickness of 0.5 nm to 15 nm.